Spirulina algae is suitable for everyone: it has a high protein content – 40 per cent more than beef – and is rich in iron and vitamins. Very soon, and (it would seem) at accessible prices, it will be possible to grow it at home. Struna, from the union of the words struttura (structure) and natura (nature), is in fact the first domestic bioreactor for growing microalgae, presented by the Politecnico di Milan – specifically by the SAPERLab laboratory – as part of the exhibition 999 una collezione di domande sull'abitare contemporaneo at the Triennale di Milano.

At the heart of the project, which brought together students, researchers and companies, lies the idea that the coexistence of humans and other living organisms within a single habitat is beneficial: it reduces anxiety and stress and aids sleep. Growing microalgae at home helps to improve air quality, increasing oxygen levels and reducing those of carbon dioxide. In addition to spirulina, the bioreactor hosts other varieties of algae, rich in unsaturated fats and natural antioxidants. The aim is to help nature develop spontaneously, in order to provide humans with plant proteins while consuming far smaller quantities of water than those required for the production of animal proteins.

The structure, made up of triangular modules, can be assembled independently, adapts to small spaces and helps to shape the domestic environment. "When we talk about innovation, we think of the digital world, but there are other expressions that the city of Milan has managed to give voice to: think of food or fashion," explains Ferruccio Resta, rector of the Politecnico di Milan. "Innovation can also be pursued through architecture, and Milan can put itself forward to place it at the centre of its own debate: we are talking about an architecture without boundaries."

Is this project confirmation of the leading role the Politecnico di Milan intends to play in research and innovation in the field of sustainability?
The Politecnico di Milan wants to play a role in innovation. It always has, ever since it was founded. Now, however, this role is no longer purely technological. Technology must look to the future: naturally, we started with energy efficiency, but sustainability does not mean only energy efficiency – it means respect for the environment. The bioreactor project encompasses all of these aspects: energy, CO2, water consumption and – another theme we are working on enormously – the integration of all of this into a single function. So it seems to me that this project captures the various souls of the Politecnico well. It is an object of design, architecture and engineering, all in the service of sustainability towards the environment and towards humanity.

Sustainability has evolved in many forms. It began as environmental sustainability, then became social and, subsequently, economic. Can we say that today the concept of innovation also goes hand in hand with that of sustainability? For a product or a project to be sustainable, must it also be innovative?
The market has realised this too – we do not need to point it out. There is no longer any type of innovation that has the possibility of developing at a market level if it is not mindful of sustainability. And we are talking about sustainability towards the environment, but also towards the individual, and about respect for human beings.

Today many people grow small vegetable gardens on their balconies. Will they one day be growing spirulina algae?
Without doubt there will be greater attention from all of us to making a part of our existence more sustainable, whether it concerns our means of transport, our work or our home; everyone certainly wants to make their own contribution. I have to say that Milan is very vibrant, in the sense that it is a city that combines a great desire for technological innovation – because it is a technological city – with a respect for social commitment. On this, I believe we could be truly competitive.

It seems that residential formulas are evolving to better interpret concepts such as transience and sustainability. Do you agree?
We certainly believe that the way we live and the way we work will change enormously. There is also a desire to share certain functions, and so architecture must be capable of interpreting this flexibility of spaces and this capacity of spaces to be repurposed. All of this in respect of what is, once again, the environment, spaces and individuals' spaces. So this type of structure and this type of project help to be flexible while at the same time interpreting change and sustainability.

Did you know that spirulina algae is recommended for students during exam time?
No, I didn't know that, but every time I learn something new (laughs).